Face mask lens attaching means



sept. 2o, 1960 Filed May 7, 1956 J. T. coREY '2,952,852

FACE MASK LENS ATTACHING MEANS 2 Sheets-Sheet 1 1N V EN TOR.

sep T UGT@ BY A Sept. 20, 1960 J. neem-:Y

FACE MASK LENS ATTACHING MEANS 2 Sheets-Sheet 2 Filed May 7, 1956INVENTR. 755e p CO7 BY m FACE MASK LENS A'I'IACHING MEANS Joseph T.Corey, Tonawanda, N.Y., assignor to Scott Aviation Corporation, acorporaon of New York Filed May 7, '1956, Ser. No. 583,001

'3 Claims. (Cl. 2-14) This invention relates to a face mask for coveringeither just the eyes of the wearer, or for covering the eyes and alsothe nose of the wearer, or for covering the entire face of the wearer.In particular, this invention relates to a novel means for detachablyattaching a transparent lens to a mask.

The main object of the invention is to provide a simple, inexpensive butrugged and duid-tight means of so securing a transparent lensl to a facemask, that said lens may be readily replaced when it becomes broken orunduly scratched. Other collateral objects of the invention andpractical solutions thereof are described in the following descriptionand illustrated in the appended drawings, wherein:

Fig. 1 is a diminutive, front elevation of a mask (with parts brokenaway) to which a lens 13 has been detachably secured by my novel lenssecuring means.

Fig. 2 is a diminutive, top plan thereof.

Fig. 3 is an enlarged, fragmentary section (with parts broken away) thruthe upper part of said lens 13, and the adjacent members of the maskassembly.

Fig. 4 is a fragmentary, horizontal section thru the mask assembly takenon line 4 4 Fig. l.

Fig. 5 is an enlarged, fragmentary, vertical section thur the upper partof a modiiied lens 13a, and the adjacent parts of the mask assembly.

Fig. 6 is an enlarged, fragmentary, vertical section thru the upper partof another modified lens 13b and the adjacent parts of the maskassembly.

F or convenience, the present invention will be described precisely asit is illustrated, but it is to be understood that the scope of theinvention is to be measured solely by the breadth of the appended claimsand by the intrinsic novelty of the invention.

The mask 7 shown is of the full face type and is provided with the usualhead straps 8 and 9, inlet tube 10 and exhalation iitting 11, all ofwhich are molded in one integral piece of somewhat stit' butnevertheless flexible rubber. In the usual and Well known manner, thismask snugly nts the face of the wearer so as to render it duidtight tothe ambient iluid or gaseous medium in which the wearer is immersed, theinside of the mask being capable of withstanding a positive orabove-ambient pressure by the provision of the usual, annular, inwardlyand forwardly projecting, thin, integral ange 12, shown in Fig. 2

Arranged in the front, upper part of the mask 7 is the transparent,plastic lens 13, and this lens is not dat but is of semi-cylindricalshape, and it is this curvilinear shape which prevents the use ofconventional lens-securing means.

This lens 13 has integrally formed in its curvilinear periphery anoutwardly-opening groove 14, and the latter is adapted to receive anannular rubber ange 15, which projects inwardly from what may be definedas a lens opening 16 of the mask 7. This flange 15 is liexible and ismolded integrally with the rest of the rubber mask 7 and while beingassembled is adapted to be snapped into aforesaid groove 14 of the lens13.

United States Patent G ice This ange 15 is mechanically held rmly in thelens groove 14, and is rendered duid-tight with respect to the lens 13as follows:

Formed annularly in the outer, medial part of said ange 15 is an annularslot or slit 17 which extends inwardly from the outer face of the mask 7but terminates short of the inner face of said ange 15. In puttingtogether the components of the mask assembly (or in replacing the lens13 .when the mask is in service) a flexible metal wire or draw cord 18is passed inwardly into the slit 17 while being tightly pulledcircumferentially and wound one or two or more times around theperiphery of the lens 13. The ends of this draw cord 18 are thenfastened or twisted together (see Fig. 3) and the excess portions ofsaid draw-cord are then snipped oli, the tied together or twisted ends20 being tucked into the slit 17 so as to be out of sight and yetrecoverable, if at some later time said twisted ends 2.0 are to be drawnout and then untwisted, and the draw-cord 18 removed, so as to enablethe lens 13 to be replaced.

It is to be noted, however, that, While this whole construction is veryeliicient, this ange 15 and the slit 17 are not strictly necessary, and,instead, the draw-cord 18 may be employed to force the adjacent parts ofthe mask 7 directly into the groove 14 to form what is in elect a ange.Theoretically, this groove 14 of the lens 13 might also be eliminated,but such a construction is not deemed to properly withstand the physicalstresses to which many masks in service are necessarily subjected.

For additional strength and also to absolutely ensure fluid tightness,the mask 7 is also provided with both a rear supplemental flange 21 anda front supplemental ange 22, both of said supplemental flangesprojecting inwardly from the lens opening 16 and being adapted to bearfirmly against the rear and front peripheral margins, respectively, ofthe lens `13.

Strictly speaking, the rear liange 2,1 is a shoulder or abutment in theform shown in the drawings, but it is deemed more convenient to speak ofit as a flange so as to be in the same nomenclatural catagory as thefront ange 22, and also because, obviously, the construction could besuch that it would undisputedly be a definite flange.

For the sake of appearance and also to prevent dirt from getting intothe slit 17, a flexible covering band 23 is provided, said band being ofannular shape (like an ordinary rubber band) and being of suicient widthto lap over the front and rear sides of the annular protuberance 2.4,which projects outwardly from the mask adjacent its lens opening '16.This lapping over of said covering band 23 over the front side of saidannular protuberance 24 permits the mask assembly to be attractive inappearance and the frame of the lens 13 to be symmetrical even tho themask 7 itself is pulled somewhat out of shape by the tension of thedraw-cord 18. The rear side of the covering band 23 laps over the rearside of said annular protuberance 24 so as to balance the forces exertedby said covering band 23 and thus prevent its crawling outwardly overthe front face of the lens 13.

Fig. 5 shows a modified form of lens 13a, which is contructed of twocomponents, a plastic lens proper 25 and an auxiliary, peripheralplastic component 26 which is substantially H shaped in cross sectionand which is cemented or otherwise secured to said lens proper 2S. Thisconstruction has the advantage that the lens proper 25 does not have tobe molded (as in Figs. 1-4) and can be constructed by either bending andcutting a sheet of plastic or a sheet of glass, or, if desired, saidlens proper 25 may be constructed of ground and polished glass which isof special importance when a prescription is to be ground into the lens.

Fig. 6 shows another modified form of plastic lens l Y 7 7 Y Y Y 3 Y 13bwhich can be constructed entirely of components each of which is stampedout of sheet material. This is eiected by cementing an annular ring 27to the lens proper I28,' and then cementing to saidring 27 a larger ring30 having a lens opening; a stijf-lens arranged in'said opening andhaving aV peripheral, outwardly-facing groove, said mask being providedwith a supplemental, annular, Yrear .flange arranged adjacent theopening of said mask and adapted to ybear against the rear, peripheralmargin Yof said lens; and means Vfor'annularly drawing tightly inwardlyupon said mask around its opening so as to press the adjacent portion ofsaid mask into said groove of said lens.

2. A face mask assembly comprising: a face mask having a. lens opening;a stili lens arranged in said opening and having a peripheral,outwardly-facing groove, said mask being provided with a supplemental,annular, front ange arranged adjacent the opening of said mask and.

`adapted to bear against the front, peripheral margin of said lens; andmeans for annularl;r drawing Vtightly inwardly upon said mask around itsopening so as to press 4 the adjacent portion of said mask into saidgroove of said lens.

3. A face mask assembly comprising: a face mask having a lens opening; astift lens arranged in said opening and having a peripheral,outwardly-facing groove, said mask being provided with a supplemental,annular, rear and front flanges arranged adjacent the opening of saidmask and adapted to bear against the rear and front, peripheral margins,respectively of said lens; and means for annularly drawing tightlyinwardly upon said mask around its opening so as to press the adjacentportion of said mask into said groove of said lens.

References Cited in the le of this patent UNITED STATES PATENTS

